Women's rights activists and pro-change protesters in Egypt have rallied to condemn a serious sexual assault on an American news reporter, Lara Logan, which took place in Cairo's Tahrir Square in the moments following Hosni Mubarak's resignation last Friday.

"Lara Logan … and her team and their security were surrounded by a dangerous element amidst the celebration," Logan's employers, CBS news, said in a brief statement. "It was a mob of more than 200 people whipped into frenzy.

"In the crush of the mob, she was separated from her crew. She was surrounded and suffered a brutal and sustained sexual assault and beating before being saved by a group of women and an estimated 20 Egyptian soldiers."

Logan, a 39-year-old foreign correspondent, had previously been detained by the Egyptian police while covering the anti-government uprising. She has now flown back to the US and is "recovering at home", CBS said. The incident has provoked a storm of comment in both the Egyptian and American blogospheres, with many protesters in Cairo keen to show that Logan's attackers were not representative of the pro-change crowds.

"It's incredibly sad that this has happened, and it's something that the spirit of Tahrir and the spirit of revolution was resolutely against," Ahdaf Soueif, an author who spent a great deal of time in Tahrir Square, told the Guardian. "Women in the square were rejoicing that they felt freedom on the streets of Cairo for the first time, and [this is] definitely something that we want to stamp out alongside corruption and all the other social ills that have befallen Egypt during Mubarak's regime."

Mahmoud Salem, a well known Egyptian blogger, was one of many 25 January activists to express outrage. "Lara Logan, what happened to you was reprehensible, I hope u don't judge the egyptian people or Tahrir because of it," he tweeted under his moniker Sandmonkey.

Some activists have suggested that the assault was the work of pro-Mubarak gangs, whose use of sexual harassment as an intimidation tactic was extensively documented during the revolution, as was their targeting of foreign reporters.

But the investigation and prosecution of sexual harassment cases is already low in Egypt, and the detention of those responsible amid the country's current institutional turmoil appears unlikely.

The harassment of women on the streets has long been a major issue in Egyptian society, although efforts to curb the problem have often met resistance from government officials.

Scepticism about the extent of the harassment extended as far as the former first lady, Suzanne Mubarak, who once accused the media of exaggerating the problem to tarnish the country's reputation.

A survey by the independent Egyptian Centre for Women's Rights in 2008, however, revealed that 83% of Egyptian women and 98% of foreign women had been exposed to some form of sexual harassment, including groping, verbal abuse, stalking and indecent exposure.

Contrary to popular opinion, the incidents did not appear to be linked to the woman's style of dress, as three-quarters of victims had been veiled at the time.

Throughout the 18 days of mass unrest that brought millions to Tahrir Square, many women reported that the level of sexual harassment there was far lower than they had expected. Protesters maintained a disciplined internal security system and, apart from clashes with police and pro-Mubarak militants, no violence was recorded inside the square.

"We Egyptian youth are so proud of this revolution, and the first thing we will do is demand that all people stop sexual harassment," said Marwa Mokhtar, a women's rights campaigner. "This is our country now, not Mubarak's country, and we will not allow harassment to continue in the new Egypt."

An Egyptian Facebook group set up to condemn the attack on Logan carried similar sentiments. "We should have continued guarding Tahrir even in the day of celebration," posted Ahmad Fahmy, a pro-change demonstrator. "I don't know what to say. Nothing we can do or say can make up for what happened. I guess for now I can just say 'Sorry' to Lara and for all women Egyptians or non-Egyptians who were harassed or assaulted in Egypt before."

The White House said that President Barack Obama had called Logan on Wednesday but gave no details of the call. In the US, debate over Logan's assault has been fierce, after some commentators made light of the incident.

Nir Rosen, an American journalist, was forced to resign from his fellowship at New York University following a series of posts on Twitter which drew jokey comparisons between Logan and CNN correspondent Anderson Cooper, who was assaulted by thugs in Egypt earlier this month, claiming "it would have been funny if it happened to Anderson too". He has since apologised for the remarks.

Rightwing blogger Debbie Schlussel also drew ire, after a post on her website blamed Logan herself for the attack.

"So sad, too bad, Lara," wrote Schlussel. "No one told her to go there. She knew the risks. And she should have known what Islam is all about. Now she knows …"

Her words were met with a chorus of objections and outrage online. "Lara Logan's assault is horrifying, but shouldn't be an excuse for the rightwing to twist this into a story about Arab misogyny," argued the Democracy Now correspondent Anjali Kamat on Twitter.

An article published in the Colombia Journalism Review in 2007 claimed that the sexual abuse of female foreign correspondents is under-reported because many victims do not come forward for fear of losing out on future assignments.

"In the mounting rhetoric, what is getting lost is the fact that a reporter has been sexually assaulted," said Laila Lalami in the Nation magazine. "[By coming forward] Lara Logan has broken a powerful taboo."

Heather Blake, of Reporters Without Borders, said that the incident should not be used to prevent female correspondents from going out into the field.

"Female journalists have distinct voices to male journalists and it is vital that those very different concerns and outlooks continue to be heard," she argued. "The attack on Lara Logan highlights the fact that there needs to be gender-specific protection and training of journalists.

"At the moment, female and male journalists have the same training. The truth is that female journalists need to be taught about different cultures and the ways in which men behave in those cultures. They need to know about gender-specific expectations in different countries, from what they wear to how they interact with those they met."

Paul Steiger, chairman of the Committee to Protect Journalists, of which Logan is a board member, said: "We have seen Lara's compassion at work while helping journalists who have faced brutal aggression while doing their jobs. She is a brilliant, courageous, and committed reporter. Our thoughts are with Lara as she recovers."